It is often necessary to transport solid articles, some of irregular shape, which require some protection, but are not so fragile as to require complete immersion in packing material. According to one well-known technique, such articles can be packed in paperboard cartons having partitions which hold the article away front the ends of the carton. One such carton is shown in U.S. Pat. No. 3,682,297, which is designed for containing tape cassettes. In the carton shown in such patent, transverse for partitions can be moved between positions opening or blocking a sleeve defined by the walls of the carton for receiving the product. In order to hold the partition in an erected position blocking the sleeve, the partition interlocks with a notch in the tuck flap of the end closure of the carton.
Other prior cartons having transverse partitions include U.S. Pat. No. 3,563,449 and U.S. Pat. No. 4,294,397. No known carton discloses a means for locking a collapsible partition in an erected position in a carton which does not include a tuck flap end closure.
In other prior art cartons, such as those disclosed in U.S. Pat. No. 2,611,529 and U.S. Pat. No. 4,260,059, flaps extending into the interior of the carton have been used to cushion articles inserted into the carton. A disadvantage of such prior cartons is that such flaps are provided by adding additional paperboard material to the blank extending away from the remainder of the carton.